Insulator



Nov. 19, 1929. J. E. MATEER I 1,736,455

INSULATOR Filed July 15, 1927 INVENTOR Jesse .C/Vafeer I BY TORNEY mama Nov. 19,1929

UNITED s ATE-s PATENT OFFICE- ml 3. HATER, OF WILKINSBUBG, PENNSYLVANIA, ASSIGNOB '10 WESTING HOUSE ELECTRIC Q KANUFAQ'IUBING GOHPANY A CORPORATION 01 PENNSYLVANIA msur.aron

Application Med July 15,- 1021. Serial at. 905,877.

My invention relates to insulators and particularly to insulators for mounting overhead trolley conductors in tunnels and similar places of limited head room.

One object of my invention is to rovide an insulator of the above-indicate character, thatshall cm by its dielectric material to maximum vantage and have substantially a maximum amount of the material for an insulator of height given to conserve head-room.

Another object ofmy invention is to provide' a tunnel insulator of inverted substantially 'frusto-conical shape that shall be rigidly supported at its upper or major-base end, proof against the admission of moisture thereto from above and have moisturevide an overhead insulator in which the dielectric material shall extend substantially throughout the length thereof and have metal terminals disposed substantially within the longitudinal limits defined by the dielectric structure.

Another object of my invention is to provide an insulator including a dielectric portion of hollow substantially frusto-conical shape that shall embody a transverse wall serving the combined functions of closure means therefore and means for bracing the same against cantilever loads.

Another object of my invention is to provide an overhead conductor-supporting tunnel insulator of hollow inverted substantially frusto-conical shape that shall have imperforate sides and be transversely closed adjacent to its upper end and that shall have breathing means ad'acent to its lower end.

Another object o my invention is to provide an insulator that shall be simple and durable in construction, economical to manufacture and effective in its operation.

In tunnels and similar locations, having limited overall height or overhead room, it-is difiicult to provide an overhead trolley conductor supporting insulator that is sufficiently strong permanent in charthat has other features tending acter, proof" against the damaging effects of condensed moisture, sufiiciently resistant to the relatively high voltages employed and to render it a generally satisfactory device.

- It is my aiinto overcome the objections attending the use of tunnel insulators heretofore "employed and that shall have other advanta es thereover.

Accor ingly, in practicing my invention It provide an insulator embodying a di-electric member of hollow inverted substantially frusto-conical shape having imperforate longitudinal-side and transverse walls, side flanges, terminal means and other features that are so constructed and related as to attain all of the objects of my invention.

Figure 1 of'the accompanying drawings isa top plan view of an insulator constructed in accordance with my invention, and

Fig. 2' is a longitudinal side view thereof, partially in section, and partially in elevation. Y

A dielectric body member 2 of substantially frusto-conical shape embodies side walls 3, a transverse wall 4, cylindrical end terminal receiving portions 6 and 7 and a plurality of longitudinally spaced annular surface-creepage flanges 9.

The member 2 is preferably constructed of porcelain with the walls 3 and 4 thereof of 7 structure as a uni Since the structure is to be rigidly mounted with its upper or major base end adjacent to the tunnel roof, the Wall 4 is disposed slight-1y inwardly from the surface 11 to better permit the insulator to be disposed level against its upper supporting means than might be the case with the upper surface of the wall 4 flush with the surface 11.

In contradistinction to frusto-conical insulators that are usually disposed with the major bases at the lower ends thereof and surface creepage flanges sloping downwardly toward the major bases. the flanges 9 of the 3 device of myinvention are preferably rovided with upper rain shedding sur aces sloping downwardly and outwardly relative to the major base. These flanges are also, preferably of downwardly successively'decreasing diameters and increasing lateral extentfrom the wall portion 3, more nearly in accordance with the voltage gradient of the insulator which is stronger at the lower or live end of the structure and not uniformly distributed between its ends. The flanges may also, be of varying shapes and spaced varying distances relative to each other, in accordance with the gradient drop adjacent to the individual flanges.

An upper terminal member 14 comprises a cylindrical or ring portion 15 that is secured, as by a body of cement 16, to the as by a body of cement 21, to the lower cylindrical portion 7 of the body 2, a relatively thin transverse wall portion 22 and laterally extending apertured holding portions 23 for mounting a trolley-conductor clamp or other device thereon.

The wall portion 22 may be provided with one or more openings 25 providing breathing means and to prevent the accumulation of condensed moisture within the body 2.

The wall portion 22 is also, preferably relatively thin to conserve the overall length of the structure and sufficiently strong to pro, vide bracing means against the end surface 12. I

By my invention, substantially a maximum amount of the dielectric material for a given length is employed and utilized to maximum advantage, a structure of relatively great strength and durability is obtained and an insulator is provided for the particular purnular side flanges of downwardly successively decreasing diameters and increasing extent from the body, and upper and lower terminals having cylindrical portions secured to said nular side flanges of downwardly successively decreasing diameters and increasing extent from the body, an upper ring terminal having portionsfor mounting the insulator, and a lower terminal having a cylindrical portion secured to said body, an apertured transverse mounting portions.-

3. An insulator comprising a hollow dielectric body of inverted substantially frustoconical'shape having an inwardly offset wall closing its'upper end, cylindrical ends and a plurality of downwardly and outwardly sloping annular side flanges of downwardly successively decreasing diameters and increasing extent from the body, an upper ring terminal having portions for mounting the insulator by turning the same, and a lower terminal having a cylindrical portion secured to said body, an apertured transverse end Wall and laterally-extending conductor-mounting portions.

In testimony whereof, I have hereunto sub scribed my name this 7th day of July, 1927.

. JESSE E. MATEER.

end wall and laterally-extending conductorposes specified that is an improvement, in

. general, over insulators for similar purposes heretofore employed.

While I have shown and described a particular form of my invention, changes may be effected therein without departing from the spirit and scope thereof as set forth in the appended claims.

I claim as my invention:

1. An insulator comprising a hollow dielectric body of inverted substantially frustoconical shape having an imperforate trans-' verse wall adjacent to its upper major-base 

